Of those, nearly 20 fixtures tested above 15 parts per billion, the Environmental Protection Agency’s limit for lead content. The district has either fixed the problem or cut off access to those fixtures.

Another 225 tested above 5 ppb — the standard for bottled water and the new target San Diego Unified has set for all of its water. Those, too, have been remediated or blocked off as the district finishes installing filters.

Lead Testing Results As Of Oct. 9, 2018

Locations marked in green tested below 5 ppb. Facilities marked in yellow tested between 5 and 15 ppb. And facilities marked in red have at least one fixture that tested above 15 ppb.

The work will be ongoing.

“We intend to maintain a quality assurance approach, where we’re doing more random testing just to make sure things are staying the same,” Chief Operations Officer Drew Rowlands said.

The district is considering setting a target as low as 1 ppb. Rowlands said that would require full replacement of plumbing systems, as well as filters. Schools that have received new fixtures and filters must still flush their systems weekly to ensure old pipes don’t leach lead over the weekend and holidays.

The district has earmarked $45 million of a $3.5 billion dollar bond on the November ballot for improving water quality in schools. The district’s previous bond also included money for improved plumbing.

Facilities that still tested above 15 ppb as of Tuesday include: Bird Rock Elementary, Cabrillo Elementary, Chollas-Mead Elementary, Encanto Elementary, Mann Middle and district headquarters. Service has been shut off to contaminated fixtures at these sites.

The district says Oakland Unified and Berkeley Unified have followed its lead in pursuing more stringent water quality thresholds.